The present patent application relates generally to a cleaning apparatus. More specifically, the present patent application relates to a mechanical air filter cleaning system and method that can be structured for use in a cleaning apparatus.
Industrial and commercial floors are cleaned on a regular basis for aesthetic and sanitary purposes. There are many types of industrial and commercial floors ranging from hard surfaces, such as concrete, terrazzo, wood, and the like, which can be found in factories, schools, hospitals, and the like, to softer surfaces, such as carpeted floors found in restaurants and offices. Different types of floor cleaning equipment, such as scrubbers and sweepers, have been developed to properly clean and maintain these different floor surfaces.
A typical scrubber is a walk-behind or drivable, self-propelled, wet process machine that applies a liquid cleaning solution from an onboard cleaning solution tank onto the floor through nozzles fixed to a forward portion of the scrubber. Rotating brushes forming part of the scrubber rearward of the nozzles agitate the solution to loosen dirt and grime adhering to the floor. The dirt and grime become suspended in the solution, which is collected by a vacuum squeegee fixed to a rearward portion of the scrubber and deposited into an onboard recovery tank.
Scrubbers can be very effective for cleaning hard surfaces. Unfortunately, debris on the floor can clog the vacuum squeegee, and thus, the floor should be swept prior to using the scrubber. Consequently, sweepers are commonly used to sweep a floor prior to using a scrubber. A typical sweeper is a self propelled, walk-behind or drivable dry process machine which picks debris off a hard or soft floor surface without the use of liquids. The typical sweeper has rotating brushes which sweep debris into a hopper or “catch bin,” Combination scrubber-sweepers have been developed that provide the sweeping and scrubbing functionality in a single unit.
Sweeper systems typically utilize a filter assembly to filter the “dirty” air that is suctioned into the hopper. The filter in the filter assembly typically comprises a conventional pleated panel filter.
One method for cleaning traditional pleated panel filters involves using mechanical vibration. This can be accomplished by vibrating the filter frame and consequently the filter media, using a “comb” to move or flick the individual pleats, or mechanically vibrating the filter media through direct contact. The latter has a detrimental effect on the pleated filter media because vibration between the media and any contacting part will wear holes in the media, which allows for dirty air to pass therethrough.
PowerCore® air filters produced by the Donaldson Company are a compact style of air fitter that was originally designed for engine air intake systems in automotive/vehicle applications. Unlike conventional pleated panel filters where a sheet of filter media is folded and the bends in the media are perpendicular to the flow of air, the PowerCore® filters contain a series of small flutes made from folded filter media that are closed on one end and are parallel to the flow of air. Dirty air enters one flute, passes through the wall of the flute and the clean air exits the other side of the filter through one of the adjacent flutes. These small flutes allow a larger amount of filter media to be packaged in the same amount of space occupied by a conventional panel filter. The advantage is that a smaller sized filter will contain the same amount of filtering area.
As of today, the only known means to clean fluted filters is with pulsed air. Particularly, the pulsed air system uses an air compressor to supply compressed air to a series of nozzles that are controlled by a solenoid valve. These nozzles are positioned over the clean side of the filter and the solenoid valve pulses short bursts of compressed air into the filter to push dust back out of the filter i.e., direction of the pulsed air flow is opposite the flow of air through the filter during normal operation).